London, United Kingdom - In revenge for trying to side with the Allies, in March 1944 the Nazis invaded Hungary and quickly forced 424,000 Hungarian Jews on the death train to Auschwitz.

Twelve-year-old Ivor Perl was one of them. He was rounded up with his parents and seven brothers and sisters from the southern town of Mako. Pretending to be 16 was the lifeline that sent him to the gruelling Allach labour camp with his father and older brother, while his mother and younger siblings were killed at Auschwitz. Only he and his brother survived.

"What life depended on was not how clever or shrewd you were," Ivor told Al Jazeera. "If you happened to be picked for the group that didn't come back, that was it."

Last April, 82-year-old Ivor returned to the Nazi concentration camp with his son David, 55. The pair joined 11,000 Jews, Gentiles, and Holocaust survivors on the March of the Living, an annual procession from Auschwitz to Birkenau in remembrance of the six million Jews murdered by the Nazis.

January 27 marks World Holocaust Memorial Day and 70 years since the Auschwitz camp's liberation. The largest of all the death factories, more than one million of the Nazis' 11 million victims perished there.

"I ask people how they came to Auschwitz," said Ivor. "They come on an air-conditioned plane, stay in a lovely four star hotel. Just think how I came here - on a cattle truck. That's when I lost all my family. How can I tell ordinary people what it meant?"

Emotionally crippled

In Britain there are about 1,000 Jewish Holocaust survivors who come under enormous pressure to share their stories with the aim that never again will these atrocities be repeated. But until this visit, Ivor was unable to talk about his memories. He kept them to himself, unaware of the emotionally crippling effect it was having on David and his three daughters.

"For me, there's always been this huge ogre of Auschwitz," said David. "Even the word struck terror in me. When we decided to come here I thought, 'I'm going back to Auschwitz.' But I've never been there."

A common belief I heard from the survivors was that crying was a weakness and would indicate Hitler had won. And yet, this is the very thing us children need to see.

- David Perl, son of Holocaust survivor

David began therapy after years of suffering from depression and marriage troubles. It resonated so much he decided to retrain as a psychotherapist himself, helping make sense of the myriad of issues Holocaust survivors and their families face.

Growing up, David was told not to upset his father. "We learned to suppress our own emotions, which is very limiting for a young child. We were afraid to ask Dad about his experiences and he didn't want to talk for fear of upsetting us. So we grew up in a family where secrets were the norm. I call it a conspiracy of silence."

Ivor resettled in London after the war, met his wife Rhoda and gradually built a business in fashion retail. Like many survivors, he was determined to be a success.

"For about 40 years, I never spoke to anyone about it," said Ivor. "I thought at the time it was the right thing to do, but looking back it was very wrong. It seemed the least hurtful way for them and the best way to make a life in the future. I didn't realise how it would affect my children."

David's sisters have also had difficulties with addictions and relationship issues.

Though there is no conclusive evidence on second generation Holocaust trauma, studies show that disturbed family relations and a difficulty in establishing parental bonds are common experiences.

50:50 club

Not far from Ivor's home in north London is the Holocaust Survivor's Centre, which provides counselling and practical support to more than 600 members. "I call it the 50:50 club," said Service Manager Aviva Trup. "Fifty percent of survivors' children believe they are negatively affected by the Holocaust, 50 say they might have been like this anyway."

Rita Goldberg's German-Jewish mother, Hilde Jacobsthal, was not a Nazi prisoner, but she spent the war running from the Gestapo.

"For me it was very hard to establish my identity and realise my life was important enough to be ambitious," said Rita, 65, now a lecturer at Harvard University. "I call it a haunting. You feel the ghost of the past."

Goldberg is the goddaughter of Otto Frank, the father of Anne Frank and her world-famous diaries. "If you knew from the time you can speak that children like you were murdered on purpose, it has an effect," she said. "In my early years I saw Otto all the time and he was always crying. I wasn't stupid. Images formed."

This April, heads of state including French President François Hollande will join thousands of Jews at Auschwitz to remember the Holocaust, celebrate Jewish unity and condemn racism. For Ivor, the terrifying decision to return eased 70 years of tortured memories and offered a thin glimmer of hope.

"I'm more than glad I've come back," he said. "It's practically saved me in a lot of ways. I've suffered and terrible things have happened. But there is another story." Ivor referred to two fellow marchers, a Muslim and a Christian who work at the National Holocaust Centre, the UK's hub for Holocaust education.

"Talking to them, I feel a tremendous sense that's the way forward."

For David, his "return" to a place he had never been before finally helped him connect with his father.

"On this journey, a lot of hate, pain and crying changed into an answer. Dad revealed that not a day goes by where he does not cry internally for his lost family. A common belief I heard from the survivors was that crying was a weakness and would indicate Hitler had won. And yet, this is the very thing us children need to see.

"The trip finally gave [Dad] the ability to tell me for the first time how much he loved me and how proud he is of me. I feel I have now integrated the knowledge into a feeling that Dad did the best he could."

Source: Al Jazeera